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Back again with N-methylpyrrolidone in API

Discussions about GC and other "gas phase" separation techniques.

5 posts Page 1 of 1
Hi all !!!..

A new year has come but troubles have not changed.

Is ther anyone who has a method to control absence of N-Methylpyrrolidone in API's. USP and EP claim taht HS/GC is not an enought sensible technic.

Any help will be appreciated.

Thanks and have a nice year !!!!!

Basil

If you can document that your procedure does meet the requirements and meets the guidelines for a validated procedure, just document it. There are updated ways to do lots of assays, and to push them through EP or USP takes time and money; lots of EP and USP procedures are long-outdated or awkward.
Hello!
We have two GC methods (it is possible also HPLC-see questions in HPLC section-we have got the answer there):
1. Column AT5 (30m x 0,53mmID x 5mcm)
FID
carrier gas: He 4ml/min
Split 1:5
Oven T:40stC (6min)-10stC/min- 150stC(5min)-3stC/min- 165stC (10min)
T inject:220stC
T det:250stC
Solvent.DMSO
We determine also other solvents so Run is long. NMP elutes after the solvent peak (RT cca 21min)
2. Column CP-SIL 5 (30m x 0,53mmID x 5mcm)
FID
carrier gas: He 5ml/min
Split 1:5
Oven T:150stC
T inject:120stC
T det:250stC
Solvent: Ether
NMP elutes after the solvent peak (RT cca 7,6min)

I hope it will help you somehow. Bye!
ana

















2.
juju

If it's applicable, HPLC methodology was referenced in this thread

Thanks juju (or ana) :lol:

We will try with your first option.

I hope we would have enought sensibility with this method (if nout I'd chandge split ratio).

I'll tell you how it works in our lab

Thanks again

Basil
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